Case 254: Posttraumatic Migrating Fat Embolus Causing Fat Emboli Syndrome.

History An otherwise healthy 18-year-old man was admitted to the emergency department with a closed displaced fracture of the left femoral shaft ( Fig 1 ) after a high-velocity motorbike accident. At admission, other physical examination findings were unremarkable. Initial unenhanced and contrast material-enhanced (120 mL of Iomeron 400; Bracco Imaging, Milan, Italy) computed tomography (CT) was performed in the arterial and venous phases from the head to the knees. No abnormalities were noted in the brain or chest at initial CT. [Figure: see text] Within a few hours, the patient developed sudden mental confusion and severe hypoxemia, with rapidly worsening tachypnea and perturbed arterial blood gas with low partial pressure of oxygen (61 mmHg [8.1 kPa]; normal range, 75-100 mmHg [10.0-13.3 kPa]) and low partial pressure of carbon dioxide (32 mmHg [4.3 kPa]; normal range, 38-42 mmHg [5.1-5.6 kPa]). A second contrast-enhanced chest CT examination and initial brain magnetic resonance (MR) imaging were performed. Femoral fracture was stabilized with external fixation, and the patient was admitted to the intensive care unit, with progressive neurologic recovery at day 3 and respiratory improvement at day 4. Treatment included intubation with mechanical ventilation and intravenous administration of steroids and noradrenaline. Afterward, the femoral fracture was stabilized with an intramedullary nail. The patient made a full neurologic recovery 1 month after the accident.